Vortex generator of an hvac unit

ABSTRACT

A vortex generator for installation in a passage defined by heating, ventilating, and air conditioning (HVAC) equipment is configured to mix air flow through the passage. The vortex generator includes a proximal end configured to extend from a support defining the passage. The proximal end includes a first width dimension configured to extend transverse to a flow direction through the passage. The vortex generator includes a distal end opposing the proximal end. The distal end includes a second width dimension configured to extend transverse to the flow direction through the passage, where the second width dimension is greater than the first width dimension. The vortex generator includes a body extending from the proximal end to the distal end. The body includes a third width dimension configured to extend transverse to the flow direction through the passage, where the third width dimension is less than the second width dimension.

BACKGROUND

This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.

Heating, ventilating, and air conditioning (HVAC) systems are generally configured to provide temperature controlled air to an internal space. Certain HVAC systems, such as an air handling unit (AHU), may include devices configured to ventilate an air flow and/or control a temperature of the air flow that is delivered to the internal space. For example, the HVAC system may receive a return air flow from the internal space, receive an outdoor air flow from an external environment, and mix the return air flow and the outdoor air flow to generate a mixed air flow delivered to the internal space. Other types of air flow mixing are also possible.

Traditional HVAC systems configured to generate mixed air flows may be expensive to manufacture and difficult to install. Further, traditional HVAC systems configured to generate mixed air flows may cause large pressure drops that lead to relatively low HVAC system efficiency (e.g., by requiring relatively high power consumption). Accordingly, it is now recognized that improved HVAC systems, such as improved AHUs, for generating mixed air flows are desired.

SUMMARY

A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below.

An embodiment of the present disclosure includes a vortex generator for installation in a passage defined by heating, ventilating, and air conditioning (HVAC) equipment is configured to mix air flow through the passage. The vortex generator includes a proximal end configured to extend from a support defining the passage. The proximal end includes a first width dimension configured to extend transverse to a flow direction through the passage. The vortex generator includes a distal end opposing the proximal end. The distal end includes a second width dimension configured to extend transverse to the flow direction through the passage, where the second width dimension is greater than the first width dimension. The vortex generator includes a body extending from the proximal end to the distal end. The body includes a third width dimension configured to extend transverse to the flow direction through the passage, where the third width dimension is less than the second width dimension.

Another embodiment of the present disclosure includes a heating, ventilating, and air conditioning (HVAC) system having a housing, a mixing plate disposed in the housing and having a surface defining a passage through the mixing plate, and a vortex generator configured to mix air flows through the passage. The vortex generator includes a proximal end disposed at the surface of the mixing plate, where the proximal end includes a first width dimension extending transverse to a flow direction through the passage. The vortex generator also includes a distal end opposing the proximal end, where the distal end includes a second width dimension extending transverse to the flow direction through the passage, and where the second width dimension is greater than the first width dimension. The vortex generator also includes a body extending between the proximal end and the distal end, where the body includes a third width dimension extending transverse to the flow direction through the passage, and where the third width dimension is less than the second width dimension.

Another embodiment of the present disclosure includes an air handling unit (AHU). The AHU includes a housing configured to receive an outside air flow via a first inlet and a return air flow via a second inlet. The AHU also includes a mixing plate disposed in the housing and having a surface defining a boundary of a passage through the mixing plate, the passage being configured to receive the outside air flow and the return air flow. The AHU also includes vortex generators extending from the surface of the mixing plate and into the passage, where the vortex generators are configured to mix the outside air flow and the return air flow to generate a mixed air flow. Each vortex generator includes a proximal end connected to the surface of the mixing plate and having a first width dimension, a body connected to the proximal end, and a distal end connected to the body opposite to the proximal end. The distal end extends into the passage and includes a second width dimension that is greater than the first width dimension of the proximal end. The first width dimension and the second width dimension are oriented transverse to a flow direction through the passage.

BRIEF DESCRIPTION OF THE DRAWINGS

Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which:

FIG. 1 is a perspective view of a heating, ventilating, and air conditioning (HVAC) system for building environmental management, in accordance with an aspect of the present disclosure;

FIG. 2 is a perspective view of an HVAC unit, such as an air handling unit (AHU), for use in the HVAC system of FIG. 1, in accordance with an aspect of the present disclosure;

FIG. 3 is a front view of a mixing plate for use in the HVAC unit of FIG. 2, in accordance with an aspect of the present disclosure;

FIG. 4 is a front view of vortex generators extending into a passage defined by a surface of the mixing plate of FIG. 3, in accordance with an aspect of the present disclosure;

FIG. 5 is a perspective view of vortex generators extending into a passage defined by a surface of the mixing plate of FIG. 3, in accordance with an aspect of the present disclosure;

FIG. 6 is a side view of a vortex generator extending into a passage defined by a surface of the mixing plate of FIG. 3, in accordance with an aspect of the present disclosure; and

FIG. 7 is a table comparing pressure drop measurements corresponding to various operating ranges of the HVAC unit of FIG. 2 with pressure drop measurements corresponding to various operation ranges of conventional air blenders, in accordance with an aspect of the present disclosure.

DETAILED DESCRIPTION

One or more specific embodiments of the present disclosure will be described below. These described embodiments are only examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terminals “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.

The present disclosure is directed to a heating, ventilating, and air conditioning (HVAC) system or unit, such as an air handling unit (AHU), having vortex generators configured to mix a return air flow and an outdoor air flow to generate a mixed air flow. In accordance with the present disclosure, the HVAC unit may include a housing with a first inlet configured to receive the return air flow (e.g., via a duct) and a second inlet configured to receive the outdoor air flow. The HVAC unit may also include a mixing plate disposed in the housing. The mixing plate may include a surface defining a boundary of a passage configured to receive the return air flow and the outdoor air flow. Vortex generators may extend from the surface of the mixing plate (e.g., the boundary of the passage) into the passage. For example, each vortex generator may include a proximal end connected to the surface, a distal end opposing the proximal end, and a body extending between (and connected to) the proximal end and the distal end. In general, a first width of the vortex generator at the proximal end may be less than a second width of the vortex general at the distal end. Further, a third width of the body of the vortex generator may be less than the second width. For example, the third width of the body of the vortex generator may be equal to the first width of the proximal end of the vortex generator.

In certain embodiments, each vortex generator may include a T-shaped cross-sectional profile having the above-described first width at the proximal end, second width at the distal end, and third width of the body. Further, in certain embodiments, each vortex generator may include a leading edge with a first height and a trailing edge with a second height that is greater than the first height. A plate extending between the leading edge and the trailing edge may define the distal end of the vortex generator, and may include a curvature that enables the second height (i.e., at the trailing edge of the vortex generator) to be greater than the first height (i.e., at the leading edge of the vortex generator).

In some embodiments, the distal end of the vortex generator may be untethered. For example, while the proximal end of the vortex generator is connected to the surface of the mixing plate and the body of the vortex generator, and while the body is connected to the proximal end and the distal end of the vortex generator, the distal end is connected only to the body of the vortex generator. Reference in the present disclosure to the distal end being untethered is intended to indicate that the distal end is connected to the body of the vortex generator but otherwise hangs freely within the passage defined by the surface of the mixing plate. The vortex generators may include certain length, width, and/or height dimensions (e.g., relative dimensions), described in detail with reference to the drawings, selected to enable and/or improve certain technical benefits described below.

The above-described configurations of the presently disclosed HVAC unit enable suitable mixing of two air flows (e.g., outside air flow and return air flow) to achieve a suitable temperature profile in the mixed air flow, while reducing a pressure drop across the mixing plate relative to conventional HVAC systems or units, thereby improving HVAC efficiency (e.g., via reduced power consumption). Further, the above-described configurations of the presently disclosed HVAC unit may reduce manufacturing costs and installation difficulties associated with the HVAC unit. These and other features are described in detail below with reference to the drawings.

Turning now to the drawings, FIG. 1 illustrates a heating, ventilating, and air conditioning (HVAC) system for building environmental management that may employ one or more HVAC units. In the illustrated embodiment, a building 10 is air conditioned by a system that includes an HVAC unit 12. The building 10 may be a commercial structure or a residential structure. As shown, the HVAC unit 12 is disposed on the roof of the building 10. However, the HVAC unit 12 may be located in other equipment rooms or areas adjacent the building 10. The HVAC unit 12 may be a single package unit containing other equipment, such as a blower, integrated air handler, and/or auxiliary heating unit. In other embodiments, the HVAC unit 12 may be part of a split HVAC system.

The HVAC unit 12 may be an air cooled device that implements a refrigeration cycle to provide conditioned air to the building 10. Specifically, the HVAC unit 12 may include one or more heat exchangers across which an airflow is passed to condition the airflow before the airflow is supplied to the building. In the illustrated embodiment, the HVAC unit 12 is an AHU, such as a rooftop unit (RTU), which conditions a supply air stream, such as environmental air and/or a return airflow from the building 10. Outdoor units, indoor units, or other conditioning schemes are also possible. After the HVAC unit 12 conditions the air, the air is supplied to the building 10 via ductwork 14 extending throughout the building 10 from the HVAC unit 12. For example, the ductwork 14 may extend to various individual floors or other sections, such as rooms, of the building 10. Terminal units 20 associated with the floors, rooms, or other sections of the building 10 may be connected to the ductwork 14 and may be configured to distribute the airflow to the floors, rooms, or other sections of the building 10. In some embodiments, the terminal units 20 may include air conditioning features in addition to, or in the alternate of, the air conditioning features of the HVAC unit 12.

In certain embodiments, the HVAC unit 12 may be a heat pump that provides both heating and cooling to the building with one refrigeration circuit configured to operate in different modes. In other embodiments, the HVAC unit 12 may include one or more refrigeration circuits for cooling an air stream and a furnace for heating the air stream. Additionally or alternatively, other HVAC equipment may be installed at the terminal units 20 or in another area of the building, such as a basement 21 (e.g., a boiler may be installed in a basement of the building 10). A control device 16, one type of which may be a thermostat, may be used to designate the temperature of the conditioned air. The control device 16 also may be used to control the flow of air from the HVAC unit 12, through the ductwork 14, to the terminal units 20, or any combination thereof. For example, the control device 16 may be used to regulate operation of one or more components of the HVAC unit 12 and/or terminal units 20. In some embodiments, other devices may be included in the system, such as pressure and/or temperature transducers or switches that sense the temperatures and pressures of the supply air, return air, and so forth. Moreover, the control device 16 may include computer systems that are integrated with or separate from other building control or monitoring systems, and even systems that are remote from the building 10.

As previously described, the HVAC unit 12 of FIG. 1 may be an AHU, such as an RTU or some other type of AHU, although other types of HVAC units are also possible. In accordance with present embodiments, configurations of the HVAC unit 12, described in detail below with reference to FIGS. 2-7, enable suitable mixing of two air flows (e.g., an outside air flow and a return air flow) to generate a mixed air flow and achieve a suitable temperature profile in the mixed air flow. Presently disclosed configurations may reduce a pressure drop in the HVAC unit 12 relative to conventional HVAC systems or units, thereby improving HVAC efficiency (e.g., via reduced power consumption). Further, configurations of the presently disclosed HVAC unit 12 may reduce manufacturing costs and installation difficulties.

FIG. 2 is a perspective view of an embodiment of the HVAC unit 12, such as an AHU, for use in the HVAC system of FIG. 1. In the illustrated embodiment, the HVAC unit 12 includes a housing 30 having a first inlet 32 (e.g., a first opening) and a second inlet 34 (e.g., a second opening). The first inlet 32 is defined in a first wall 36 (e.g., a top wall) of the housing 30 and the second inlet 34 is defined in a second wall 38 (e.g., a front wall) of the housing 30, where the first wall 36 and the second wall 38 are coupled at or along an edge 39 of the housing 30. The first inlet 32 may be an outside air inlet configured to receive outside air, while the second inlet 34 may be a return air inlet configured to receive return air (e.g., from a conditioned space). Other air flows and arrangements are also possible. In certain embodiments, ducts may be coupled to the first inlet 32 and/or the second inlet 34 and configured to supply the respective air flows (e.g., an outside air flow corresponding to the first inlet 32 and a return air flow corresponding to the second inlet 34).

The first inlet 32 and the second inlet 34 may be fluidly coupled with a mixing plenum 40 defined by the housing 30 and having a mixing plate 42 disposed therein. For example, the mixing plenum 40 may include an upstream compartment 44 and a downstream compartment 46 separated by the mixing plate 42. The upstream compartment 44 may receive the air flows from the first inlet 32 and the second inlet 34. A fan or blower (not shown) may draw the air flows through the first inlet 32 and the second inlet 34 and bias the air flows toward and through a passage 50 in the mixing plate 42. The fan or blower may be internal to the housing 30, such as within the downstream compartment 46 or a separate compartment 47 of the housing 30. In another embodiment, the fan or blower may be disposed in a separate area of the HVAC unit 12 and/or the HVAC system having the HVAC unit 12.

The mixing plate 42 may include a surface 48 defining the passage 50 through which the air flows corresponding to the first inlet 32 and the second inlet 34 are directed (e.g., by the fan or blower). In the illustrated embodiment, the passage 50 defined by the surface 48 includes a hexagonal shape, although other shapes (e.g., a circle, a triangle, a square, a rectangle, a pentagon, a heptagon, an octagon, etc.) are also possible. The air flows corresponding to the first inlet 32 and the second inlet 34 may pass from the upstream compartment 44, through the passage 50 defined by the surface 48 of the mixing plate 42, and into the downstream compartment 46. A flow direction 54 from the upstream compartment 44, through the passage 50, and into the downstream compartment 46 is labeled in FIG. 2. It should be noted that the flow direction 54 indicates a general flow direction through the mixing plenum 40 and should not be taken to mean that the air flow(s) and/or individual air particles passing through the mixing plenum 40 are biased (e.g., by the fan or blower) perfectly parallel to the illustrated flow direction 54. Instead, the flow direction 54 illustrated in FIG. 2 is intended to refer to a general direction of flow through the mixing plenum 40 and is used in later discussion as a reference frame regarding other features of the HVAC unit 12. In other words, the flow direction 54 in the illustrated embodiment passes through a center of the hexagonal shape of the passage 50 and is tangent to a plane of the hexagonal shape.

The mixing plate 42 in the illustrated embodiment includes vortex generators 52 extending from the surface 48 of the mixing plate 42 into the passage 50. While FIG. 2 only labels three of the vortex generators 52 for sake of clarity, it should be understood that the vortex generators 52 may be disposed on all segments (or sides) of the shape (e.g., hexagonal shape) formed by the surface 48 defining the passage 50. That is, while only three vortex generators 52 are labeled in FIG. 2 for sake of clarity, the mixing plate 42 in FIG. 2 includes three vortex generators 52 on each segment (or side) of the hexagonal shape formed by the surface 48 defining the passage 50 (e.g., for a total of eighteen).

FIG. 3 is a front view of an embodiment of the mixing plate 42 for use in the HVAC unit 12 of FIG. 2, in which eighteen vortex generators 52 are illustrated and labeled, three on each segment (or side) of the hexagonal shape defined by the surface 48 and corresponding passage 50. For example, as illustrated and labeled in FIG. 3, a first segment 56 of the surface 48 defining the passage 50 having the hexagonal shape includes three of the vortex generators 52 extending therefrom. The surface 48 has six segments including the first segment 56. In certain embodiments, the six segments include common dimensions and/or common numbers of vortex generators 52 (e.g., three on each segment).

Focusing again on FIG. 2, the vortex generators 52 are configured to mix the air flow corresponding to the first inlet 32 (e.g., the outside air flow) with the air flow corresponding to the second inlet 34 (e.g., return air flow). The outside air flow, for example, may include a different (e.g., higher) temperature than the return air flow. By mixing the outside air flow and the return air flow, the vortex generators 52 may generate a mixed air flow in the downstream compartment 46 having a more uniform temperature profile than would otherwise be possible without the mixing plate 42 and corresponding vortex generators 52. That is, the temperature profile of the mixed air flow in the downstream compartment 46 may be more even (e.g., closer to uniform or homogenous) than the temperature profile of the air flows in the upstream compartment 44. The more uniform temperature profile in the mixed air flow (e.g., in the downstream compartment 46) may be more suitable for use in conditioning an internal space of a building serviced by the HVAC unit 12.

Further, in accordance with certain embodiments and discussed in more detail below with reference to later drawings, distal ends of the vortex generators 52 may be untethered. That is, the distal ends of the vortex generators 52 may hang freely in the passage 50. The untethered distal ends, in addition to certain other geometric aspects of the vortex generators 52, may reduce a pressure drop caused by the mixing plate 42 relative to traditional embodiments (e.g., traditional embodiments in which members extend from one segment or side of a passage to an another segment or side of the passage). By reducing the pressure drop relative to traditional embodiments, HVAC efficiency may be improved (e.g., via reduced power consumption relative to traditional embodiments).

Focusing again on FIG. 3, the passage 50 and the mixing plate 42 may include certain dimensions (e.g., relative dimensions) selected to enable or improve technical benefits (e.g., reduced pressure drop while maintaining adequate air mixing) in accordance with the present disclosure. For example, the passage 50 may include a tip 51 (or in some embodiments a segment) spaced from a side 53 of the mixing plate 42 by a first distance 55. The passage 50 may include a segment (such as the segment 56) paced from top 57 of the mixing plate 42 by a second distance 59. Further, the side 53 of the mixing plate 42 may include a height 61 and the top 57 of the mixing plate 42 may include a length 63. In one embodiment, the first distance 55 is approximately 368 millimeters (approximately 14.49 inches), the second distance 59 is approximately 275 millimeters (approximately 10.83 inches), the height 61 is approximately 1371.6 millimeters (approximately 54 inches), and the length 63 is approximately 1651 millimeters (approximately 65 inches). However, embodiments in accordance with the present disclosure encompass dimensions that vary from those described above. Further, embodiments of the present disclosure may be scaled up or down in size. In general, a ratio between the first distance 55 and the second distance 59 may be between 1:1 and 3:2, and a ratio between the height 61 and the length 63 may be between 2:3 and 1:1. It should also be noted that the hexagonal shape of the passage 50 in the illustrated embodiment may be rotated (e.g., 90 degrees) relative to, for example, the top 57 of the mixing plate 42, such that the tip 51 faces the top 57 of the mixing plate 42 instead of the side 53 of the mixing plate 42. As previously described, other shapes and orientations of the passage 50 are also possible.

FIG. 4 is a front view of an embodiment of the vortex generators 52 extending into the passage 50 defined by the surface 48 of the mixing plate 42 of FIG. 3. FIG. 5 is a perspective view of an embodiment of the vortex generators 52 extending into the passage 50 defined by the surface 48 of the mixing plate 42 of FIG. 3. For example, FIGS. 4 and 5 include the segment 56 (or side) of the surface 48 defining the passage 50 having the hexagonal shape illustrated in FIG. 3, where three vortex generators 52 extend from the segment 56 of the surface 48. In the embodiments illustrated in FIGS. 4 and 5, each vortex generator 52 includes a proximal end 58 connected to the surface 48 and a distal end 60 opposing the proximal end 58. Each vortex generator 52 also includes a body 62 extending between the proximal end 58 and the distal end 60 of the corresponding vortex generator 52.

As clearly illustrated in FIG. 5, the distal end 60 of each vortex generator 52 may include a curved plate that slopes away from the surface 48 from a leading edge 64 of the vortex generator 52 to a trailing edge 66 of the vortex generator 52. Continuing with FIG. 5, the vortex generators 52 may each include a T-shaped cross-sectional profile at the leading edge 64, at the trailing edge 66, and between the leading edge 64 and the trailing edge 66. The curvature of the plate defining the distal end 60 of the vortex generator 52 may enable a first height dimension 70 of the vortex generator 52 at the leading edge 64 that is less than a second height dimension 72 of the vortex generator 52 at the trailing edge 66 of the vortex generator 52. The height dimensions 70, 72 of each vortex generator 52 are generally transverse (e.g., substantially perpendicular) to the flow direction 54 illustrated in FIG. 5. In an embodiment of the present disclosure, the first height dimension 70 may be approximately 10 millimeters (approximately 0.39 inches) and the second height dimension 72 may be approximately 30 millimeters (approximately 1.18 inches), where the first height dimension 70 and the second height dimension 72 are measured from the surface 48 (e.g., where the proximal end 58 begins) to an upper surface of the curved plate defining the distal end 60 of the vortex generator 52. However, embodiments in accordance with the present disclosure encompass dimensions that vary from those described above. Further, embodiments of the present disclosure may be scaled up or down in size. In general, a ratio between the first height dimension 70 and the second height dimension 72 may be between 1:4 and 1:2. Further, it should be noted that the second height dimension 72 of the vortex generator 52 (e.g., at the trailing edge 66 of the vortex generator) may represent a maximum height of the vortex generator 52.

Continuing again with FIG. 5, a length dimension 73 of each vortex generator 52 may generally correspond to (e.g., be substantially equal to) a length dimension 75 of the surface 48 of the mixing plate 42, where the length dimensions 73, 75 extend generally parallel to the flow direction 54. The length dimensions 73, 75 may be, for example, approximately 60 millimeters (approximately 2.36 inches). However, embodiments in accordance with the present disclosure encompass dimensions that vary from those described above. Further, embodiments of the present disclosure may be scaled up or down in size. In general, a ratio between the first height dimension 70 of the vortex generator 52 (i.e., at the leading edge 64 of the vortex generator 52) and the length dimension 73 of the vortex generator 52 may be between 1:8 and 1:5.

Turing back to FIG. 4, width dimensions of the vortex generators 52 and the segment 56 of the surface 48 defining the passage 50 are shown. For example, the proximal end 58 and the body 62 of each vortex generator 52 may include a first width dimension 74 that is less than a second width dimension 76 of the distal end 60 of the vortex generator 52. The width dimensions 74, 76 extend generally transverse to (e.g., substantially perpendicular to) the flow direction 54. While the proximal end 58 and the body 62 of each vortex generator 52 share the first width dimension 74 in the embodiment illustrated in FIG. 4, in other embodiments, the proximal end 58 may include a different width than the body 62. The first width dimension 74 may be approximately 5 millimeters (approximately 0.2 inches) and the second width dimension 76 may be approximately 45 millimeters (approximately 1.77 inches). However, embodiments in accordance with the present disclosure encompass dimensions that vary from those described above. Further, embodiments in accordance with the present disclosure may be scaled up or down in size. In general, a ratio between the first width dimension 74 and the second width dimension 76 may be between 1:20 and 1:6.

Spacing between the vortex generators 52 is also illustrated in FIG. 4. For example, a first distance dimension 80 between adjacent vortex generators 52 (e.g., as measured from any consistent points of two adjacent vortex generators 52, such as a right-side tip of one vortex generator 52 and another right-side tip of an adjacent vortex generator 52) may be approximately 128.5 millimeters (approximately 5.06 inches). A second distance dimension 82 of the segment 56 of the surface 48 may be approximately 457.5 millimeters (approximately 18.01 inches). However, embodiments in accordance with the present disclosure encompass dimensions that vary from those described above. Further, embodiments in accordance with the present disclosure may be scaled up or down in size. In general, a ratio between the first distance dimension 80 and the second distance dimension 82 may be between 1:5 and 1:3. FIG. 6 is a side view of an embodiment of one of the vortex generator 52 illustrated in FIGS. 2-5, including an illustration of the length dimension 75, the first height dimension 70 at the leading edge 64 of the vortex generator 52, and the second height dimension 72 at the trailing edge 66 of the vortex generator 52, to further clarify the features described in detail below. The length dimension 75, the first height dimension 70, and the second height dimension 72 are described in detail above with reference to FIGS. 4 and 5.

FIG. 7 is an embodiment of a table 100 comparing pressure drop measurements corresponding to various operating ranges of the HVAC unit 12 of FIG. 2 with pressure drop measurements corresponding to various operation ranges of conventional air blenders. For example, the table 100 includes scenarios 102 in which different temperatures 104 of outdoor air/return air 106 and air flow rates 100 are tested in the HVAC unit 12 of the present disclosure and compared against a conventional air blender. The table 100 also includes a results section 110 indicating conventional air blender pressure drop measurements 112 and vortex generator pressure drop measurements 114 (i.e., the measurements 114 correspond to presently disclosed embodiments). As can be seen in the results section 110 of the illustrated table 100, presently disclosed embodiments reduce a pressure drop relative to the conventional air blender.

One or more of the disclosed embodiments, alone or in combination, may provide one or more technical effects useful in manufacturing, installing, and operating an HVAC unit and corresponding equipment. For example, the above-described configurations of the presently disclosed HVAC unit enable suitable mixing of two air flows (e.g., outside air flow and return air flow) to achieve a suitable temperature profile in the mixed air flow, while reducing a pressure drop across the mixing plate relative to conventional HVAC units or systems, thereby improving HVAC efficiency (e.g., via reduced power consumption). Further, the above-described configurations of the presently disclosed HVAC unit may reduce manufacturing costs and installation difficulties.

While only certain features and embodiments of the disclosure have been illustrated and described, many modifications and changes may occur to those skilled in the art, such as variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters including temperatures and pressures, mounting arrangements, use of materials, colors, orientations, etc., without materially departing from the novel teachings and advantages of the subject matter recited in the claims. The order or sequence of any process or method steps may be varied or re-sequenced according to alternative embodiments. It is, therefore, to be understood that the appended claims are intended to cover all such modifications and changes as fall within the true spirit of the disclosure. Furthermore, in an effort to provide a concise description of the exemplary embodiments, all features of an actual implementation may not have been described, such as those unrelated to the presently contemplated best mode of carrying out the disclosure, or those unrelated to enabling the claimed disclosure. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation specific decisions may be made. Such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure, without undue experimentation. 

1. A vortex generator for installation in a passage defined by heating, ventilating, and air conditioning (HVAC) equipment, wherein the vortex generator is configured to mix air flow through the passage and the vortex generator comprises: a proximal end configured to extend from a support defining the passage, wherein the proximal end comprises a first width dimension configured to extend transverse to a flow direction through the passage; a distal end opposing the proximal end, wherein the distal end comprises a second width dimension configured to extend transverse to the flow direction through the passage, and wherein the second width dimension is greater than the first width dimension; and a body extending from the proximal end to the distal end, wherein the body comprises a third width dimension configured to extend transverse to the flow direction through the passage, and wherein the third width dimension is less than the second width dimension.
 2. The vortex generator of claim 1, comprising a leading edge and a trailing edge, wherein at least one of the first width dimension, the second width dimension, or the third width dimension is constant from the leading edge to the trailing edge.
 3. The vortex generator of claim 2, wherein the first width dimension is constant from the leading edge to the trailing edge, the second width dimension is constant from the leading edge to the trailing edge, and the third width dimension is constant from the leading edge to the trailing edge.
 4. The vortex generator of claim 1, wherein the first width dimension is equal to the third width dimension such that the proximal end, the body, and the distal end form a T-shaped cross-sectional profile of the vortex generator.
 5. The vortex generator of claim 1, wherein a ratio between the first width dimension and the second width dimension is between 1:20 and 1:6.
 6. The vortex generator of claim 1, comprising a leading edge and a trailing edge, wherein a first height dimension of the vortex generator at the leading edge is less than a second height dimension of the vortex generator at the trailing edge.
 7. The vortex generator of claim 6, wherein a ratio between the first height dimension and the second height dimension is between 1:4 and 1:2.
 8. The vortex generator of claim 6, wherein the distal end comprises a plate having a curvature from the leading edge to the trailing edge.
 9. A heating, ventilating, and air conditioning (HVAC) system, comprising: a housing; a mixing plate disposed in the housing and having a surface defining a passage through the mixing plate; and a vortex generator configured to mix air flows through the passage, the vortex generator comprising: a proximal end disposed at the surface of the mixing plate, wherein the proximal end comprises a first width dimension extending transverse to a flow direction through the passage; a distal end opposing the proximal end, wherein the distal end comprises a second width dimension extending transverse to the flow direction through the passage, and wherein the second width dimension is greater than the first width dimension; and a body extending between the proximal end and the distal end, wherein the body comprises a third width dimension extending transverse to the flow direction through the passage, and wherein the third width dimension is less than the second width dimension.
 10. The HVAC system of claim 9, wherein the vortex generator comprises a leading edge and a trailing edge, and wherein at least one of the first width dimension, the second width dimension, or the third width dimension is constant from the leading edge to the trailing edge.
 11. The HVAC system of claim 9, wherein the proximal end, the body, and the distal end form a T-shaped cross-sectional profile of the vortex generator.
 12. The HVAC system of claim 9, wherein the vortex generator comprises a plate defining the distal end of the vortex generator between a leading edge of the vortex generator and a trailing edge of the vortex generator, such that a first height dimension of the vortex generator at the leading edge is less than a second height dimension of the vortex generator at the trailing edge.
 13. The HVAC system of claim 9, wherein a ratio of the first width dimension to the second width dimension is between 1:20 and 1:6
 14. The HVAC system of claim 9, wherein the housing comprises: a first air flow inlet configured to receive a return air flow; and a second air flow inlet configured to receive an outside air flow, wherein the vortex generator is configured to mix the return air flow and the outside air flow to generate a mixed air flow.
 15. The HVAC system of claim 9, comprising a plurality of vortex generators including the vortex generator, wherein the plurality of vortex generators is configured to mix the air flows through the passage.
 16. An air handling unit (AHU), comprising: a housing configured to receive an outside air flow via a first inlet and a return air flow via a second inlet; a mixing plate disposed in the housing and comprising a surface defining a boundary of a passage through the mixing plate, the passage being configured to receive the outside air flow and the return air flow; and a plurality of vortex generators extending from the surface of the mixing plate and into the passage, wherein the plurality of vortex generators is configured to mix the outside air flow and the return air flow to generate a mixed air flow, and wherein each vortex generator of the plurality of vortex generators comprises: a proximal end connected to the surface of the mixing plate and having a first width dimension; a body connected to the proximal end; and a distal end connected to the body opposite to the proximal end, wherein the distal end extends into the passage and comprises a second width dimension that is greater than the first width dimension of the proximal end, the first width dimension and the second width dimension being oriented transverse to a flow direction through the passage.
 17. The AHU of claim 16, wherein the distal end of each vortex generator of the plurality of vortex generators comprises an untethered distal end.
 18. The AHU of claim 16, wherein each vortex generator of the plurality of vortex generators comprises a leading edge and a trailing edge, the leading edge having a first height dimension that is less than a second height dimension of the trailing edge.
 19. The AHU of claim 16, wherein each vortex generator of the plurality of vortex generators comprises a curvilinear plate defining the distal end of the vortex generator and extending between a leading edge of the vortex generator and a trailing edge of the vortex generator.
 20. The AHU of claim 16, wherein a ratio of the first width dimension to the second width dimension is between 1:20 and 1:6. 